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Can you have if-then-else logic in SQL? [duplicate]
...SE statement is the closest to an IF statement in SQL, and is supported on all versions of SQL Server:
SELECT CASE <variable>
WHEN <value> THEN <returnvalue>
WHEN <othervalue> THEN <returnthis>
ELSE <returndefaultcase>
...
How do I (or can I) SELECT DISTINCT on multiple columns?
I need to retrieve all rows from a table where 2 columns combined are all different. So I want all the sales that do not have any other sales that happened on the same day for the same price. The sales that are unique based on day and price will get updated to an active status.
...
to drawRect or not to drawRect (when should one use drawRect/Core Graphics vs subviews/images and wh
...bviews whenever you can. You can be more productive, and take advantage of all the OO mechanisms that should things easier to maintain. Use Core Graphics when you can't get the performance you need out of UIKit, or you know trying to hack together drawing effects in UIKit would be more complicated....
How do I get currency exchange rates via an API such as Google Finance? [closed]
...
Thanks for all your answers.
Free currencyconverterapi:
Rates updated every 30 min
API key is now required for the free server.
A sample conversion URL is: http://free.currencyconverterapi.com/api/v5/convert?q=EUR_USD&compact=y
F...
How to append data to div using JavaScript?
...
theDiv.appendChild(content);
Using innerHTML:
This approach will remove all the listeners to the existing elements as mentioned by @BiAiB. So use caution if you are planning to use this version.
var theDiv = document.getElementById("<ID_OF_THE_DIV>");
theDiv.innerHTML += "<YOUR_CONTENT&...
stdlib and colored output in C
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All modern terminal emulators use ANSI escape codes to show colours and other things.
Don't bother with libraries, the code is really simple.
More info is here.
Example in C:
#include <stdio.h>
#define ANSI_COLOR_RE...
Can I use my existing git repo with openshift?
... openshift repo with your local bitbucket clone. You do that by issuing locally:
git merge openshift/master -s recursive -X ours
With this command you tell git to merge the master branch in the openshift git repo with your local git repo. You tell it to merge using the recursive merging strategy a...
Using Regex to generate Strings rather than match them
...elps me to generate loads of data for performance testing. It would be really cool to be able to specify a regex for Strings so that my generator spits out things which match this. Is there something out there already baked which I can use to do this? Or is there a library which gets me most of...
Is there an MD5 Fixed Point where md5(x) == x?
...ng. Assuming that the MD5 sum of any string is uniformly distributed over all possible sums, then the probability that any given 128-bit string is a fixed point is 1/2128.
Thus, the probability that no 128-bit string is a fixed point is (1 − 1/2128)2128, so the probability that there is a fixed ...
Capistrano - clean up old releases
Usually when using capistrano, I will go and manually delete old releases from a deployed application. I understand that you can run cap deploy:cleanup but that still leaves 5 releases. Is this it's intended purpose? Is there another way to cleanup old releases to just 1 previous deploy?
...